1. Field of the Invention
The present invention relates to a power supply apparatus and a method for providing a voltage, and more particularly relates to a power supply apparatus, which can automatically adjust the output voltage, and the method thereof.
2. Description of the Prior Art
A power supply usually provides only a fixed output voltage. When a couple of different voltages are required, a user should prepare either several different power supplies, each of which provides a specific fixed output voltage, or a power supply that provides a limited number of different output voltages selectable by user switching. However, this kind of power supply should be switched manually to a desired voltage corresponding to different output objectives, and therefore it is inconvenient to use such power supplies. In addition, a stock of too many power supplies is uneconomic and hard to manage.